The user gets 50 coins when he has created 1 block. The coins can be used (they "mature") when 120 blocks have been generated by the whole network after he created the block.

If the network grows very large and that makes it difficult to get your transaction into a block for free, you can make it happen faster by paying a small transaction fee to the node that puts your transaction into the block chain. Bitcoin supports this functionality.

Will this eventually become the world's first million-dollar pizza?

I sold 15,000 BTC on Bitcoin Market for ~0.003 USD: the all-time low on any market, AFAIK. I had measured my power consumption and determined that it only cost me ~0.001 BTC to make one BTC, so I thought 0.003 was a good profit margin. I knew the price would rise over time due to the deflationary nature of Bitcoin, but I didn't think it would happen so suddenly.

Please remember that there will only ever be 21,000,000 bitcoins created !